JP2010228604A - Parking device of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking device of an automatic transmission preventing interference of a parking rod to an inner wall face of a housing recessed part. <P>SOLUTION: In this parking device, a stopper part 28g for on which a parking rod 26 is suppressed from interfering with the inner wall face of the storing recessed part 2d by entering the inside of the storing recessed part 2d is provided at a back side from a cam holding part 28a of a sleeve 28 in the storing recessed part 2d so that it substantially faces the cam holding part 28a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a parking device for an automatic transmission that locks a transmission shaft to wheels by shifting a shift lever to a parking range.

  In this type of parking device, a parking pawl that locks the wheels by meshing with the parking gear and a receiving recess formed in the transmission case are inserted into the receiving recess in conjunction with the parking shift operation of the shift lever. A parking rod that enters, a cam that is axially movable to the parking rod and biased in a direction that engages with the parking pole by a spring, and an opening of the receiving recess are mounted on the cam. And a sleeve for engaging the parking pole with the parking gear (see, for example, Patent Document 1).

JP 2008-51174 A

  By the way, in the conventional parking apparatus, when the parking pole is bounced by the parking gear during the parking shift operation, there is a concern that the parking rod interferes with the inner wall surface of the housing recess and causes a crack. For example, if an erroneous operation is performed such as operating the shift lever to the parking range while driving, the parking pole will be bounced without meshing with the parking gear. The rod also swings violently, and the tip of the parking rod may be strongly hit against the inner wall surface of the housing recess.

  The present invention has been made in view of the above-described conventional situation, and an object thereof is to provide a parking device for an automatic transmission that can prevent a parking rod from interfering with an inner wall surface of a housing recess.

  According to the first aspect of the present invention, there is provided between a parking position that is housed in the transmission case and engages with the parking gear to lock the transmission shaft to the wheels, and a parking release position that releases the engagement with the parking gear. A parking pole that is pivotally supported and biased in the parking release direction by a return spring, and is inserted into a housing recess that protrudes from the transmission case so as to be able to advance and retreat, and interlocks with the parking shift operation of the shift lever. A parking rod that enters the inner part of the housing recess, a cam that is attached to the parking rod so as to be movable in the axial direction, and is biased in a direction to engage with the parking pole by a spring, It is attached to the opening, and when the parking rod enters, the cam engages to rotate the parking pole to the parking position. A parking device for an automatic transmission comprising a sleeve having a cam holding portion that is open on the parking pole side, wherein the parking rod is housed in the housing recess at a position deeper than the cam holding portion of the sleeve. The stopper part which suppresses interfering with the inner wall face of this accommodation recessed part by approaching into a recessed part is provided so that it may substantially oppose the said cam holding part.

  According to a second aspect of the present invention, in the parking device for an automatic transmission according to the first aspect, the stopper portion is formed integrally with the sleeve.

  According to the parking device of the first aspect of the present invention, since the stopper portion is provided on the back side of the cam holding portion in the housing recess so as to substantially face the cam holding portion, the parking rod swings by the stopper portion. Therefore, the parking rod can be prevented from interfering with the inner wall surface of the housing recess, and cracks can be prevented from occurring.

  In the invention of claim 2, since the stopper portion is formed integrally with the sleeve, it is possible to easily perform the assembling work when the parking rod is assembled to the transmission case.

1 is a side view of an automatic transmission according to Embodiment 1 of the present invention. It is a perspective view of the parking apparatus of the automatic transmission. It is a cross-sectional top view of the said parking apparatus. It is a side view of the parking device. It is a cross-sectional front view which shows the parking range position of the said automatic transmission. It is a cross-sectional front view which shows the drive range position of the said automatic transmission. It is a side view of the accommodation recessed part of the said parking apparatus. It is a cross-sectional front view which shows operation | movement of the parking rod of the said parking apparatus. It is a figure of the sleeve of the parking device. It is a characteristic view which shows the relationship between a vehicle speed, the frequency | count of interference, and generated distortion.

  Embodiment 1 of the present invention will be described below with reference to the accompanying drawings.

  1 to 9 are views for explaining a parking device for an automatic transmission according to a first embodiment of the present invention. In this embodiment, the terms front and rear and left and right mean front and rear and left and right when viewed in the forward direction of the vehicle.

  In the figure, reference numeral 1 denotes an automatic transmission mounted on an automobile. The automatic transmission 1 includes a V-belt type continuously variable transmission mechanism 3 that continuously outputs engine rotation between a low speed and a high speed in a transmission case 2, and rotation from the continuously variable transmission mechanism 3. It has a schematic structure that accommodates left and right output shafts 4 and 4 that are transmitted to left and right wheels (not shown).

  The belt-type continuously variable transmission mechanism 3 includes a primary shaft 6 to which rotation of the crankshaft 5 is transmitted, a secondary shaft 7 disposed on the vehicle rear side in parallel with the primary shaft 6, and a primary sheave of the primary shaft 6. 8 and a V-belt 10 connected to the secondary sheave 9 of the secondary shaft 7. The rotation of the secondary shaft 7 is transmitted to the left and right output shafts 4 via a differential gear mechanism (not shown).

  The transmission case 2 is of a three-part type comprising a case main body in which the continuously variable transmission mechanism 3 is accommodated, and left and right cover members bolted to the left and right mating surfaces of the case main body. is there. An oil pan 11 is bolted and fixed to the lower joint surface of the case body 2.

  A valve body 15 having a hydraulic circuit corresponding to each range position of P-R-N-D-S-B is disposed in the transmission case 2. A manual valve 16 for switching the hydraulic circuit according to each range is inserted into the valve body 15 so as to be movable in the axial direction.

  The manual valve 16 is connected to a shift operation transmission member 17 that transmits a shift operation of a shift lever (not shown) disposed in the vicinity of the driver's seat. This shift lever is for manually switching the shift position to one of the ranges P-R-N-D-S-B.

  The shift operation transmission member 17 is vertically fixed to the front end portion of the transmission case 2 and is supported on the upper end portion of the control shaft 18. The operation shaft (not shown) is fixed to the upper end portion of the control shaft 18. Rotating arm 19 to which the shift lever is connected, and a lower end portion of the control shaft 18 are fixed so as to extend in a direction perpendicular to the axis, and the rotation of the control shaft 18 is moved in the axial direction of the manual valve 16. And a switching lever 20 for conversion.

  A generally fan-shaped detent plate 21 that holds the control shaft 18 in any range position is fixed to the upper portion of the control shaft 18. The detent plate 21 has a plurality of grooves 21a formed on the outer edge according to each range, and a roller 22a supported by the elastic support plate 22 is engaged with any one of the grooves 21a.

  The automatic transmission 1 is housed in the transmission case 2 and includes a parking device that locks the transmission shaft to the wheels when the shift lever is shifted to the parking range.

  This parking device is formed in the parking gear 7 a formed integrally with the secondary shaft 7, the parking pole 25 disposed in the upper part of the transmission case 2 in the vehicle front-rear direction, and the transmission case 2. A parking rod 26 movably inserted into the housing recess 2d, a cam 27 disposed on the parking rod 26, and a sleeve 28 disposed at the inlet of the housing recess 2d. Specifically, it has the following structure.

  The parking pole 25 has a belt plate shape extending in the front-rear direction, a rear end portion of which is formed with a meshing portion 25a bent downward, and a front end portion of which is formed with a notch cam contact portion 25b. .

  The parking pole 25 includes a parking position A at which the meshing portion 25a meshes with the parking gear 7a and a parking release position at which the meshing is released by a pin 29 supported on the mating surface of the case body 2a and the left cover member 2b. B is supported so as to be rotatable up and down.

  The parking pole 25 is constantly urged by the return spring 30 in the parking release direction. Here, the meshing portion of the parking pole 25 and the parking gear 7a is set so as to mesh when the vehicle is stopped or when the vehicle speed is below a predetermined vehicle speed of extremely low speed.

  The housing recess 2d has a bottomed cylindrical shape that is integrally formed with the left cover member 2b so as to protrude outward in the vehicle width direction. Mounting seats 2e and 2e for fixing the sleeve 28 are formed at the opening edge of the housing recess 2d of the left cover member 2b.

  On the lower wall portion of the housing recess 2d, a substantially V-shaped groove 2f is formed so as to extend to the innermost part (see FIGS. 7 and 8). The concave groove 2f prevents the parking rod 26 from interfering with the housing concave portion 2d when it moves up and down. Load receiving portions 2g and 2g are formed on both edge portions of the concave groove 2f.

  The parking rod 26 is arranged in the vehicle width direction so as to intersect the parking pole 25, and is bent downwardly following the rod body 26b inserted into the housing recess 2d and the rear end of the rod body 26b. And a base portion 26a.

  The base portion 26 a is connected to the detent plate 21. As a result, when the detent plate 21 rotates with the rotation of the control shaft 18, the parking rod 26 moves to the parking range position where it enters the innermost part of the receiving recess 2d, and to the front side of the receiving recess 2d. It moves forward and backward with respect to the reverse B range position (see FIGS. 5 and 6).

  The cam 27 has a truncated cone shape having a tapered portion 27a and a large diameter portion 27b, and is mounted on the rod body 26b of the parking rod 26 so as to be movable in the axial direction.

  A spring receiving seat 26c is formed at the rear end of the rod body 26b, and a spring 31 is interposed between the spring receiving seat 27c and the cam 27. By means of the spring 31, the cam 27 is constantly urged in the direction in which it engages with the cam contact portion 25b of the parking pole 25, and is supported so as to be positioned at the longitudinal intermediate portion of the rod body 26b.

  The sleeve 28 is made of sheet metal formed by press molding, and is attached to the opening 2h of the housing recess 2d.

  The sleeve 28 includes a substantially semicircular cam holding portion 28a that can be engaged with the large diameter portion 27b of the cam 27, and a tapered guide portion 28d formed on the front edge of the cam holding portion 28a. It has front and rear flange portions 28b, 28b that protrude forward and rearward from the cam holding portion 28a.

  The guide portion 28d is for facilitating the climbing of the large diameter portion 27b onto the cam holding portion 28a when the tapered portion 27a of the cam 27 abuts. The front and rear flange portions 28b are fixed to the mounting seat 2e of the left cover member 2b by bolts 34, 34.

  A notch portion 28c opened to the parking pole 25 side is formed in the upper portion on the front side of the cam holding portion 28a, and the cam contact portion 25b of the parking pole 25 is located in the notch portion 28c. .

  The sleeve 28 is integrally formed with a circular inlay portion 28e that extends to the back side following the cam holding portion 28a and abuts against the inner peripheral surface of the opening 2h of the housing recess 2d.

  The sleeve 28 is integrally formed with a rod restricting portion 28f extending to the back side following the spigot portion 28e. The rod restricting portion 28f is formed in a vertically long hole shape so as to have an opening area smaller than the opening area of the spigot portion 28e (see FIGS. 9A and 9B).

  The rod restricting portion 28f includes a stopper portion 28g formed so as to form a substantially flat surface, front and rear vertical wall portions 28h and 28h extending and bent downward from both side edges of the stopper portion 28g, and the front, A lower wall portion 28i formed to connect the lower edges of the rear vertical wall portion 28h.

  The width dimension of the front and rear vertical wall portions 28h is set so as to abut against the parking rod 26 and restrict the movement of the parking rod 26 in the front-rear direction (see FIG. 3). The lower wall portion 28i is formed in a downward arc shape along the outer peripheral shape of the parking rod 26 so as to be positioned slightly below the cam holding portion 28a.

  The stopper portion 28g is located on the back side of the cam holding portion 28a and is disposed on the opposite side of the cam holding portion 28a so as to substantially face the cam holding portion 28a.

  The stopper portion 28g is formed in a step-down shape inwardly following the spigot portion 28e, and the lower surface of the stopper portion 28g is formed when the parking pole 25 is positioned at the parking position A. The stepped dimension is set so as to be positioned by a dimension a from the lower surface of the sheet, specifically, for example, about 0.8 mm below.

  When the shift lever is shifted to the parking range, the detent plate 21 is rotated together with the control shaft 18, the parking rod 26 enters the innermost part of the housing recess 2 d, and the cam 27 is moved by the urging force of the spring 31. It rides on the cam holding part 28a. At the same time that the large diameter portion 27b of the cam 27 is engaged with the cam holding portion 28a, the cam contact portion 25b of the parking pole 25 abuts, and the parking pole 25 is rotated upward against the urging force of the return spring 30. Move. Thereby, the meshing portion 25a of the parking pole 25 meshes with the parking gear 7a.

  When the shift lever is shifted to a range other than the parking range, the cam 27 moves backward together with the parking rod 26 and the engagement with the parking pole 25 is released, and the parking pole 25 is held at the parking release position B by the return spring 30. The

  By the way, if an erroneous operation is performed such as shifting the shift lever to the parking range during traveling, the parking pole 25 is struck by the parking gear 7a, so that the parking pole 25 vibrates up and down, and parking is performed accordingly. There is a concern that the tip of the rod 26 interferes with the inner wall surface of the housing recess 2d.

  The cause of the interference of the parking rod 26 is considered to be due to the following mechanism.

  When the parking pole 25 is bounced by the parking gear 7a, the parking pole 25 strikes the cam 27 by the reaction, and the cam 27 compresses and retracts the spring 31 (see the two-dot chain line in FIG. 8). Subsequently, the cam 27 hits the guide portion 28d of the sleeve 28 with an impact force due to the repulsive force of the compressed spring 31. As a result, the parking rod 26 jumps up to the parking pole 25 side, and the parking gear 7a is impacted via the parking pole 25. Join. Bounce from the parking gear 7a is increased and transmitted from the parking pole 25 to the parking rod 26, and the tip of the parking rod 26 interferes with the lower wall portion of the housing recess 2d.

  On the other hand, in this embodiment, since the stopper portion 28g is formed on the back side of the cam holding portion 28a of the sleeve 28 so as to substantially face the cam holding portion 28a, the parking rod 26 is moved in the vertical direction by the stopper portion 28g. Vibration can be restricted, and the parking rod 26 can be prevented from interfering with the inner wall surface of the housing recess 2d, so that the housing recess 2d can be prevented from cracking. That is, the stopper 28g suppresses the parking rod 26 from jumping up, so that the reaction caused by the jumping up is suppressed and interference with the housing recess 2d is avoided. In particular, since the stopper portion 28g is positioned slightly below the parking pole 25 at the parking position, the parking rod 26 can be more reliably prevented from jumping up.

  Further, since the concave groove 2f is formed in the lower wall portion of the housing recess 2d, interference with the housing recess 2d due to the vertical movement of the parking rod 26 can also be suppressed from this point.

  In the present embodiment, since the stopper portion 28g is formed integrally with the sleeve 28, the assembling work when the parking rod 26 is assembled to the transmission case 2 can be easily performed.

  10 (a) and 10 (b) are characteristic diagrams showing the results of experiments conducted to confirm the effect of adopting the sleeve of this embodiment.

  In this experiment, the number of interferences / s of the parking rod when shifting to the parking range during traveling at a vehicle speed of 10 to 50 km / h / s (FIG. 10 (a)) and the maximum generated strain (FIG. 10 (b)) were examined. It was.

  In FIG. 10A and FIG. 10B, the solid line K1 indicates the investigation result of the comparative example when the solid line K1 includes the sleeve according to the present embodiment. In the present embodiment sleeve, the a dimension in FIG. 9B is 0.8 mm, while the comparative example sleeve has an a dimension of −1.7 mm. That is, in the comparative example sleeve, the lower surface of the stopper portion 28g is positioned 1.7 mm above the lower surface of the parking pole 25 at the parking position A. Note that the maximum generated strain in FIG. 10B was measured on the outer wall on the back side of the interference portion with the lower wall portion of the housing recess 2d.

As is clear from the figure, in the case of the comparative example K2, when the vehicle speed is 20 km / h, the most interference occurs at 37 to 38 times / s, and the maximum distortion is 300 to 450 × 10 ^{− in the} entire region. ⁶

On the other hand, in this example K1, it is found that the interference frequency is greatly reduced as compared with the comparative example K2 at the degree of interference 2 to 3 times / s when the vehicle speed is 10 km / h. Karu. Further, the maximum generated strain is as low as 90 × 10 ⁻⁶ or less over the entire vehicle speed.

  The dimension a of the stopper portion 28g of the sleeve 28 is not limited to 0.8 mm in the above-described embodiment, and the above-described embodiment is performed after securing an interference gap with the parking rod in a state where it is not repelled by the parking gear. What is necessary is just to set suitably by experiment confirmation like an example.

  Moreover, in the said Example, although the stopper part was integrally formed in the sleeve, in this invention, it is also possible to form a stopper part in the inner wall of an accommodation recessed part.

  In the above embodiment, the automatic transmission equipped with the V-belt type continuously variable transmission mechanism has been described as an example. However, the present invention is also applicable to an automatic transmission equipped with a multi-plate clutch type transmission mechanism.

DESCRIPTION OF SYMBOLS 1 Belt type automatic transmission 2 Transmission case 2d Housing recessed part 7a Parking gear 25 Parking pole 26 Parking rod 27 Cam 28 Sleeve 28a Cam holding part 28g Stopper part 30 Return spring 31 Spring A Parking position B Parking release position

Claims (2)

It is housed in the transmission case, and is supported so as to be rotatable between a parking position that locks the transmission shaft to the wheels by meshing with the parking gear and a parking release position that releases meshing with the parking gear, And a parking pole urged in the parking release direction by the return spring,
A parking rod that is inserted into an accommodation recess formed in the transmission case so as to be able to advance and retreat, and enters the inner part of the accommodation recess in conjunction with a parking shift operation of a shift lever;
A cam attached to the parking rod so as to be movable in the axial direction and biased in a direction to engage with the parking pole by a spring;
A sleeve that is attached to the opening of the housing recess, engages with a cam when the parking rod enters, rotates the parking pawl to a parking position, and has a cam holding portion that is open on the parking pawl side. Automatic transmission parking device,
A stopper portion that prevents the parking rod from interfering with the inner wall surface of the housing recess when the parking rod enters the housing recess is provided on the back side of the cam holding portion of the sleeve in the housing recess. A parking device for an automatic transmission, wherein the parking device is provided so as to be substantially opposed to the vehicle. In the automatic transmission parking device according to claim 1,
The automatic transmission parking device, wherein the stopper portion is formed integrally with the sleeve.

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